bug#48669: Inconsistent overlay placement between minibuffer-message and set-minibuffer-message

[Juri Linkov]

> Would it make sense to change this behaviour (i.e. overlay
> configuration) so that it is consistent in both functions?

Thanks for the very useful suggestion.  This could be fixed
with the following patch where I tried to sync everything
overlay-related from set-minibuffer-message to minibuffer-message:

diff --git a/lisp/minibuffer.el b/lisp/minibuffer.el
index ffb74235e8..cb12226c07 100644
--- a/lisp/minibuffer.el
+++ b/lisp/minibuffer.el
@@ -741,7 +741,8 @@ minibuffer-message
                 ;; Don't overwrite the face properties the caller has set
                 (text-properties-at 0 message))
       (setq message (apply #'propertize message 
minibuffer-message-properties)))
-    (let ((ol (make-overlay (point-max) (point-max) nil t t))
+    (let* ((ovpos (minibuffer--message-overlay-pos))
+           (ol (make-overlay ovpos ovpos nil t t))
           ;; A quit during sit-for normally only interrupts the sit-for,
           ;; but since minibuffer-message is used at the end of a command,
           ;; at a time when the command has virtually finished already, a C-g
@@ -755,8 +756,14 @@ minibuffer-message
               ;; The current C cursor code doesn't know to use the overlay's
               ;; marker's stickiness to figure out whether to place the cursor
               ;; before or after the string, so let's spoon-feed it the pos.
-              (put-text-property 0 1 'cursor t message))
+              (put-text-property 0 1 'cursor 1 message))
             (overlay-put ol 'after-string message)
+            ;; Make sure the overlay with the message is displayed before
+            ;; any other overlays in that position, in case they have
+            ;; resize-mini-windows set to nil and the other overlay strings
+            ;; are too long for the mini-window width.  This makes sure the
+            ;; temporary message will always be visible.
+            (overlay-put ol 'priority 1100)
             (sit-for (or minibuffer-message-timeout 1000000)))
         (delete-overlay ol)))))